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Nymphaea tetragona Georgi (Nymphaceae) is traditionally used in Asia for the treatment of diarrhea, dysentery and fever. The plant contains various active compounds, including methyl gallate (MG) which are reported to inhibit bacterial virulence mechanisms. This study aimed to evaluate the alterations on viability, membrane potential and integrity of Salmonella enterica Serovar Typhimurium exposed to MG in combination with Tylosin (Ty), which is relatively inactive against Gram-negative bacteria, but it is commonly used as a feed additive in livestock. Besides, the effects of sub-inhibitory concentrations of the combination (MT) on the interaction between S. Typhimurium and the host cell, as well as on the indirect host responses, were characterized. Flow cytometry, confocal and electron microscopic examinations were undertaken to determine the effects of MT on S. Typhimurium. The impacts of sub-inhibitory concentrations of MT on biofilm formation, as well as on the adhesion, invasion and intracellular survival of S. Typhimurium were assessed. The result demonstrated significant damage to the bacterial membrane, leakage of cell contents and a reduction in the membrane potential when treated with MT. Sub-inhibitory concentrations of MT significantly reduced (P < 0.05) the biofilm-forming, adhesive and invasive abilities of S. Typhimurium. Exposure to MT drastically reduced the bacterial count in macrophages. Up-regulation of interleukin (IL)-6, IL-8 and IL-10 cytokine genes were detected in intestinal epithelial cells pre-treated with MT. This report is the first to describe the effects of MT against S. Typhimurium. The result indicates a synergistic interaction between MG and Ty against S. Typhimurium. Therefore, the combination may be a promising option to combat S. Typhimurium in swine and, indirectly, safeguard the health of the public. [ABSTRACT FROM AUTHOR]

Structural and individual level factors in prisons create challenges towards detection and management of HIV/tuberculosis. WHO and India’s HIV/tuberculosis control programs recommend intensified case finding in prisons. Low HIV and tuberculosis detection rates suggest poor implementation of existing surveillance strategies within the prison healthcare system in Mizoram’s capital city of Aizawl. We explored the operational feasibility of implementing the intensified case finding strategy in Aizawl central prison. We implemented the intensified screening through entry screening of new inmates, mass screening of resident inmates and exit screening at release. We set up digital chest radiography, sputum smear microscopy and HIV testing facilities within the prison and referral to external facility for Cartridge Based Nucleic Acid Amplification Test (CBNAAT). We screened 738 inmates (Male: 626; Female: 112). Of 53% inmates having presumptive tuberculosis symptoms, 37% underwent sputum microscopy. We detected 14 new tuberculosis cases; overall tuberculosis positivity 1.9%. We tested 65% of 657 inmates for HIV, of which 41 new cases were detected; overall HIV positivity 16.5%. Three male inmates had HIV-tuberculosis co-infection. It is feasible to implement intensified case detection for tuberculosis/HIV in the prison with inter-departmental coordination, albeit with certain challenges. [ABSTRACT FROM AUTHOR]

Background: Developing countries still struggle with late detection and mortality from pertussis. A review of clinical case definitions is necessary for early disease detection. This paper aimed to study possible clinical characteristics for earlier pertussis detection in a sporadic setting. Methods: We conducted a retrospective review of medical and laboratory records in a general paediatric ward of a district hospital in a developing country. Inclusion criteria were all children hospitalised with nasopharyngeal swab taken for Bordetella pertussis. We compared sensitivity and specificity of World Health Organization diagnostic criteria with other clinical characteristics. Polymerase chain reaction Bordetella pertussis was the gold standard used. Results: Out of 207 eligible admissions, the study retrieved 128 complete records. Approximately half of the children were less than 3 months old. The World Health Organization diagnostic criteria had a low sensitivity (15%), but high specificity (92%). In comparison, combinations that included paroxysmal cough, ill contact and facial congestion had higher sensitivity. Increasing cough duration improved specificity while compromising sensitivity. Conclusion: Several clinical characteristics such as paroxysmal cough, facial congestion and a history of ill contact have potential for early clinical detection. Conventional emphasis on cough duration may hamper early detection. [ABSTRACT FROM AUTHOR]

Defining occupational latent tuberculosis infection (LTBI) risk among healthcare workers is needed to support implementation of prevention guidelines. Prospective cohort study of 200 medical residents and nursing students in India was conducted May 2016—December 2017. Tuberculin skin test (TST) and QuantiFERON TB Gold Test-in-tube (QFT-GIT) were performed at study entry and 12 months. Primary outcome was incident LTBI (≥10mm TST induration and/or ≥0.35IU/mL QFT-GIT) at 12 months; secondary outcomes included baseline LTBI prevalence and risk factors for incident and prevalent LTBI using Poisson regression. Among 200, [90 nursing students and 110 medical residents], LTBI prevalence was 30% (95% CI, 24–37); LTBI incidence was 26.8 (95% CI, 18.6–37.2) cases per 100 person-years and differed by testing method (28.7 [95% CI, 20.6–38.9] vs 17.4 [95% CI, 11.5–25.4] cases per 100 person-years using TST and QFT-GIT, respectively). Medical residents had two-fold greater risk of incident LTBI than nursing students (Relative Risk, 2.16; 95% CI, 1.05–4.42). During study period 6 (3%) HCWs were diagnosed with active TB disease. Overall, median number of self-reported TB exposures was 5 (Interquartile Range, 1–15). Of 60 participants with prevalent and incident LTBI who were offered free isoniazid preventive therapy (IPT), only 2 participants initiated and completed IPT. High risk for LTBI was noted among medical residents compared to nursing students. Self-reported TB exposure is underreported, and uptake of LTBI prevention therapy remains low. New approaches are needed to identify HCWs at highest risk for LTBI. [ABSTRACT FROM AUTHOR]

Background: Population Services International (PSI) Myanmar’s social franchise network of general practitioners, known as Sun Quality Health Clinics (SQHC), provided tuberculosis (TB) diagnosis and treatment with Direct Observed Treatment Short course (DOTs) across Myanmar since 2004, with a total of 898 clinics across the country. People who sought TB treatment from these SQHC by themselves were regarded as walk-in patients. To augment TB case notification, PSI Myanmar developed two treatment seeking channels: Community Health Services Providers (CHSP) and Interpersonal Communicators (IPC). They actively sought people who were suspected to have TB and referred them to SQH clinics. In this study, we compared the loss to follow-up rates of TB patients across three treatment seeking channels; and investigated risk-factors for loss to follow-up. Methods and findings: A retrospective cohort design was applied using TB client records between 2012 and 2016. Outcome was defined as loss to follow-up in comparison to successful TB treatment (completed or cured). Multivariate Poisson regression was conducted to estimate incidence rate ratio of loss to follow-up. Of the 62,664 TB patients registered at the SQHC, around 10% each were actively screened by the CHSP and the IPC, and 78.9% were walk-in patients. Overall cumulative incidence for loss to follow-up rate was significantly higher in the IPC channel (14.2%, 95% CI 13.4–15.1%) than walk-in patients (8.9%, 95% CI 8.6–9.1%) and the CHSP channel (5.5%, 95% CI 5.0–6.1%) (p<0.001). The median time after which patients were lost to follow-up from treatment was 4.04 months. We found that patients with older age, male sex, patients residing in hilly region, unknown smear status, retreated cases, HIV co-infection, and unknown HIV status were risk-factors for loss to follow-up in the continuation phase of treatment; whereas patients with higher initial body weight, patients who received travel support and patients taking treatment in older providers were less likely to be lost to follow-up. Conclusions: Based on these findings, we recommend that implementation strategies for improving case notification and treatment seeking should carefully consider retention strategies in parallel, and the identified influencing factors for loss to follow-up should be taken account for such consideration. [ABSTRACT FROM AUTHOR]

Background: China has a substantial tuberculosis (TB) disease burden and an aging population. Seniors have a higher risk of developing TB disease compared to younger age groups. Active case finding (ACF) could help identify seniors with TB disease. Methods: From March to June 2017, we included ACF during annual physical check-ups for persons aged ≥ 65 years in Bayi, Sichuan Province. Seniors with clinical TB symptoms (i.e., cough lasting ≥ 2 weeks and/or hemoptysis) or one or more risk factors (e.g., previous TB disease, diabetes, and heavy alcohol consumption) were offered chest x-rays. We used acid-Fast Bacilli smear and solid culture laboratory testing for TB confirmation. We calculated the yield (i.e., cases identified among seniors screened) and cost per new each TB case detected. Focus group-interviews were conducted with health care workers and seniors to evaluate project acceptability. Participation rates and acceptability were used to assess feasibility. Results: Of the 2,393 seniors residing in Bayi, 2,049 (85.6%) were enrolled in the pilot project. Of these seniors, 794 (38.7%) presented with at least one TB risk factor and 74 (3.6%) had symptoms consistent with active TB disease. Three seniors (0.2%)–each presenting with at least one risk factor—were diagnosed with active TB. The project yielded 146 TB cases per 100,000 seniors screened; the cost per case detected was $4,897. Most workers supported ACF if additional resources and staff could be provided. Seniors appreciated the convenience of this integrated health service approach. Conclusions: Although the yield was lower than expected, ACF appeared feasible in Bayi. Targeting seniors with at least one known TB risk factor could help detect previously unidentified TB cases. However, similar projects in communities with a higher TB prevalence are needed to further evaluate the yield and required resources prior to implementation on a larger scale. Findings from our pilot project should be combined with data from these future ACF projects to improve TB screening criteria. [ABSTRACT FROM AUTHOR]

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is increasingly used for rapid bacterial identification. Studies of Burkholderia pseudomallei identification have involved small isolate numbers drawn from a restricted geographic region. There is a need to expand the reference database and evaluate B. pseudomallei from a wider geographic distribution that more fully captures the extensive genetic diversity of this species. Here, we describe the evaluation of over 650 isolates. Main spectral profiles (MSP) for 26 isolates of B. pseudomallei (N = 5) and other Burkholderia species (N = 21) were added to the Biotyper database. MALDI-TOF MS was then performed on 581 B. pseudomallei, 19 B. mallei, 6 B. thailandensis and 23 isolates representing a range of other bacterial species. B. pseudomallei originated from northeast and east Thailand (N = 524), Laos (N = 12), Cambodia (N = 14), Hong Kong (N = 4) and Australia (N = 27). All 581 B. pseudomallei were correctly identified, with 100% sensitivity and specificity. Accurate identification required a minimum inoculum of 5 x 107 CFU/ml, and identification could be performed on spiked blood cultures after 24 hours of incubation. Comparison between a dendrogram constructed from MALDI-TOF MS main spectrum profiles and a phylogenetic tree based on recA gene sequencing demonstrated that MALDI-TOF MS distinguished between B. pseudomallei and B. mallei, while the recA tree did not. MALDI-TOF MS is an accurate method for the identification of B. pseudomallei, and discriminates between this and other related Burkholderia species. [ABSTRACT FROM AUTHOR]